There is a lot of weird history with the mowing of vacant lots in Detroit from private volunteer groups tackling the effort to local gardens getting mowed over and finally an entirely new department formed to deal with it – General Services Division, which now controls the Parks Department and more recently the Recreation Department.
If you have a garden and are concerned about it being mowed over the website guidance notes:
“In cases where block clubs, homeowners, or community organizations maintain gardens or generally maintain the lot themselves, please place a 3-4’ wooden stake on the front of the property. The wooden stake should be painted hot pink at the top or have a secured hot pink ribbon tied on it.
If vacant lots are not clearly marked crews may cut the lot.”